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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=dse -S | FileCheck %s
target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
declare void @readnone_may_throw() readnone
declare void @use(ptr)
; Tests where the pointer/object is accessible after the function returns.
; Cannot remove the store from the entry block, because the call in bb2 may throw.
define void @accessible_after_return_1(ptr noalias %P, i1 %c1) {
; CHECK-LABEL: @accessible_after_return_1(
; CHECK-NEXT: store i32 1, ptr [[P:%.*]], align 4
; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: store i32 0, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5:%.*]]
; CHECK: bb2:
; CHECK-NEXT: call void @readnone_may_throw()
; CHECK-NEXT: store i32 3, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5]]
; CHECK: bb5:
; CHECK-NEXT: call void @use(ptr [[P]])
; CHECK-NEXT: ret void
;
store i32 1, ptr %P
br i1 %c1, label %bb1, label %bb2
bb1:
store i32 0, ptr %P
br label %bb5
bb2:
call void @readnone_may_throw()
store i32 3, ptr %P
br label %bb5
bb5:
call void @use(ptr %P)
ret void
}
; Cannot remove the store from the entry block, because the call in bb3 may throw.
define void @accessible_after_return6(ptr %P, i1 %c.1, i1 %c.2) {
; CHECK-LABEL: @accessible_after_return6(
; CHECK-NEXT: entry:
; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
; CHECK: bb2:
; CHECK-NEXT: store i32 1, ptr [[P]], align 4
; CHECK-NEXT: ret void
; CHECK: bb3:
; CHECK-NEXT: call void @readnone_may_throw()
; CHECK-NEXT: store i32 2, ptr [[P]], align 4
; CHECK-NEXT: ret void
; CHECK: bb4:
; CHECK-NEXT: store i32 3, ptr [[P]], align 4
; CHECK-NEXT: ret void
;
entry:
store i32 0, ptr %P
br i1 %c.1, label %bb1, label %bb2
bb1:
br i1 %c.2, label %bb3, label %bb4
bb2:
store i32 1, ptr %P
ret void
bb3:
call void @readnone_may_throw()
store i32 2, ptr %P
ret void
bb4:
store i32 3, ptr %P
ret void
}
; Tests where the pointer/object is *NOT* accessible after the function returns.
; The store in the entry block can be eliminated, because it is overwritten
; on all paths to the exit. As the location is not visible to the caller, the
; call in bb2 (which may throw) can be ignored.
define void @alloca_1(i1 %c1) {
; CHECK-LABEL: @alloca_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[P:%.*]] = alloca i32
; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: store i32 0, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5:%.*]]
; CHECK: bb2:
; CHECK-NEXT: call void @readnone_may_throw()
; CHECK-NEXT: store i32 3, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5]]
; CHECK: bb5:
; CHECK-NEXT: call void @use(ptr [[P]])
; CHECK-NEXT: ret void
;
entry:
%P = alloca i32
store i32 1, ptr %P
br i1 %c1, label %bb1, label %bb2
bb1:
store i32 0, ptr %P
br label %bb5
bb2:
call void @readnone_may_throw()
store i32 3, ptr %P
br label %bb5
bb5:
call void @use(ptr %P)
ret void
}
; The store in the entry block can be eliminated, because it is overwritten
; on all paths to the exit. As the location is not visible to the caller, the
; call in bb3 (which may throw) can be ignored.
define void @alloca_2(i1 %c.1, i1 %c.2) {
; CHECK-LABEL: @alloca_2(
; CHECK-NEXT: [[P:%.*]] = alloca i32
; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: store i32 0, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5:%.*]]
; CHECK: bb2:
; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
; CHECK: bb3:
; CHECK-NEXT: call void @readnone_may_throw()
; CHECK-NEXT: store i32 3, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5]]
; CHECK: bb4:
; CHECK-NEXT: store i32 5, ptr [[P]], align 4
; CHECK-NEXT: br label [[BB5]]
; CHECK: bb5:
; CHECK-NEXT: call void @use(ptr [[P]])
; CHECK-NEXT: ret void
;
%P = alloca i32
store i32 1, ptr %P
br i1 %c.1, label %bb1, label %bb2
bb1:
store i32 0, ptr %P
br label %bb5
bb2:
br i1 %c.2, label %bb3, label %bb4
bb3:
call void @readnone_may_throw()
store i32 3, ptr %P
br label %bb5
bb4:
store i32 5, ptr %P
br label %bb5
bb5:
call void @use(ptr %P)
ret void
}
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